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Java

Posted by Derek Derek
Derek Derek
8,744 Points

java finding matching numbers algorithm between two sorted arrays

Hi! I am trying to write a java code that given two sorted arrays, looks for matching numbers. However, I am getting errors and cannot identify what error it is, but I think there is an error in every iteration of my loops.

Here's what I have:

import java.util.ArrayList;

public class MatchingNumbers {

    private final int[] mArray1 = [13, 27, 35, 40, 49, 55, 59];
    private final int[] mArray2 = [17, 35, 39, 40, 55, 58, 60];

    public static void main(String[] args) {
        find(mArray1, mArray2);
    }

    public static void find(int[] s1, int[] s2) {
        List<Integer> storage = new ArrayList<Integer>();
        for (int i = 0; i <= s1.length; i++) {
            for (int j = 0; j <= s2.length; j++) {
                if (s2[j] == s1[i]) {
                    storage.add(s2[j]);
                    break;
                }
            }
            break;
        }
        System.out.println(storage);

    }
}

I'd appreciate any help!!!

2 Answers

Ken Alger
STAFF
Ken Alger
Treehouse Teacher
Ken Alger
Ken Alger
Treehouse Teacher

Hyun;

Would something like this work for you?

import java.util.ArrayList;
import java.util.List;

class Main {

    private static final int[] mArray1 = {13, 27, 35, 40, 49, 55, 59};
    private static final int[] mArray2 = {17, 35, 39, 40, 55, 58, 60};    

  public static void main(String[] args) {
    System.out.println("Matching Numbers");
    System.out.println("Length of Array1: " + mArray1.length);   //  For debugging purposes
    System.out.println("Length of Array2: " + mArray2.length);  //  For debugging purposes
    find(mArray1, mArray2);
  }

      public static void find(int[] s1, int[] s2) {
        List<Integer> storage = new ArrayList<Integer>();
        for (int i = 0; i <= s1.length-1; i++) {
            for (int j = 0; j <= s2.length-1; j++) {
                if (s2[j] == s1[i]) {
                    storage.add(s2[j]);
                    System.out.println(storage);   //  For debugging purposes
                    continue;
                }
            }
            continue;
        }
        System.out.println(storage);

    }
}

Post back with questions.

Happy coding,
Ken

Derek Derek
Derek Derek
8,744 Points

Thank you so much!

Ken Alger
Ken Alger
Treehouse Teacher
Ken Alger
Ken Alger
Treehouse Teacher

Pleased it worked out.

Derek Derek
Derek Derek
8,744 Points

Ken Alger, I am also learning Python, and if you know Python, do you mind helping me out writing the above code in Python? This is what I have so far:

def matching():
    a = [13, 27, 35, 40, 49, 55, 59]
    b = [17, 35, 39, 40, 55, 58, 60]
    c = []
    count = 0
    for i in range(len(a)):
        for j in range(len(b)):
            if b[j] == a[i]:
                c.append(b[j])
                count += 1
                continue
            elif b[j] > a[i] or b[j] < a[i]:
                continue

        print(count)
        print(c)

        return 1

Thank you!

Ken Alger
STAFF
Ken Alger
Treehouse Teacher
Ken Alger
Ken Alger
Treehouse Teacher

I would be pleased to take a whack at it, but you should probably start a new thread for your Python code. So as not to confuse folks with different languages in the same thread. :smile: